Search for η

We measured missing mass spectrum of the ^{12}C(γ,p) reaction for the first time in coincidence with potential decay products from η^{'} bound nuclei. We tagged an (η+p) pair associated with the η^{'}N→ηN process in a nucleus. After applying kinematical selections to reduce backgrounds, no signal events were observed in the bound-state region. An upper limit of the signal cross section in the opening angle cosθ_{lab}^{ηp}<-0.9 was obtained to be 2.2 nb/sr at the 90% confidence level. It is compared with theoretical cross sections, whose normalization ambiguity is suppressed by measuring a quasifree η^{'} production rate. Our results indicate a small branching fraction of the η^{'}N→ηN process and/or a shallow η^{'}-nucleus potential.

Inhibitory effect of statins on inflammatory cytokine production from human bronchial epithelial cells.

Statins are 3-hydroxy-3-methylglutaryl-co-enzyme A reductase inhibitors of cholesterol biosynthesis, and have been reported to exert pleiotropic effects on cellular signalling and cellular functions involved in inflammation. Recent reports have demonstrated that previous statin therapy reduced the risk of pneumonia or increased survival in patients with community-acquired pneumonia. However, the precise mechanisms responsible for these effects are unclear. In the present study, we examined the effects of statins on cytokine production from lipopolysaccharide (LPS)-stimulated human bronchial epithelial cells (BEAS-2B). Interleukin (IL)-6 and IL-8 mRNA expression and protein secretion in LPS-stimulated cells were inhibited significantly by the lipophilic statin pitavastatin and the hydrophilic statin pravastatin. As these inhibitory effects of statin were negated by adding mevalonate, the anti-inflammatory effects of statins appear to be exerted via the mevalonic cascade. In addition, the activation levels of Ras homologue gene family A (RhoA) in BEAS-2B cells cultured with pitavastatin were significantly lower than those without the statin. These results suggest that statins have anti-inflammatory effects by reducing cytokine production through inhibition of the mevalonic cascade followed by RhoA activation in the lung.

Specific detection of phosphatidylinositol 3,4,5-trisphosphate binding proteins by the PIP3 analogue beads: an application for rapid purification of the PIP3 binding proteins.

Phosphatidylinositol (PI) 3-kinase is known as one of the key molecules involved in the various biological events such as vesicle trafficking, cytoskeletal rearrangements and cell survival. T clarify the molecular basis underlying these events, we have tried to identify the proteins that can interact with phosphatidylinositol 3,4,5-trisphosphate (PIP3), the lipid product of PI3-kinase. Using a new PIP3 analogue, PIP3-APB, we synthesized an affinity column for PIP3 binding proteins. This enabled us to purify and identify several PIP3 binding proteins such as Tec tyrosine kinase, Gap1m, and Akt, as the candidates for the downstream molecules of PI3-kinase. All of these proteins contain PH domains, possible binding sites for phospholipids. Studies with various deletion mutants of Tec or Gap1m revealed that their PH domains are indeed the binding sites for PIP3. These results demonstrate that this PIP3-analogue binds various PIP3 binding proteins with high specificity and may be useful to elucidate the downstream mechanisms of PI3-kinases-mediated signaling pathways.

Evidence that 3'-phosphorylated polyphosphoinositides are generated at the nuclear surface: use of immunostaining technique with monoclonal antibodies specific for PI 3,4-P(2).

Phosphatidylinositol (PI) 3,4-P(2) is a phosphoinositide that has been shown to be important for signal transduction in growth factor stimulation. We have produced monoclonal antibodies specific for PI 3,4-P(2), which were able to detect PI 3,4-P(2) generated in 293T cells treated with H(2)O(2), or in MKN45/BD110 cells expressing activated PI 3-kinase in immunostaining. Prolonged treatment with 0.05% Tween 20 resulted in detection of staining not only at the plasma membrane, but also at the nuclear surface, indicating that 3'-phosphorylated phosphoinositides can be generated and function in the nucleus.

Interaction of marine toxin dolastatin 10 with porcine brain tubulin: competitive inhibition of rhizoxin and phomopsin A binding.

Dolastatin 10, a cytostatic peptide containing several unique amino acid subunits, was isolated from the marine shell-less mollusk Dolabella auricularia. It inhibits microtubule assembly at concentrations below 5.0 microM (IC50, 3.0 microM) and causes formation of tubulin aggregates at higher (> 10 microM) concentrations in a somewhat different manner from that caused by vinblastine. Electron microscopical analysis showed irregular aggregates of microtubule proteins in the presence of 10 microM dolastatin 10. Dolastatin 10 inhibited the binding of both radiolabeled rhizoxin and phomopsin A to tubulin with inhibition constants (Ki) of 7 x 10(-8) M and 1 x 10(-7) M, respectively. The results suggest that at least one of the binding sites of dolastatin 10 on tubulin is the rhizoxin binding site.

Isolation and structure of an antimitotic cyclic peptide, ustiloxin F: chemical interrelation with a homologous peptide, ustiloxin B.

Ustiloxin F, a microtubule inhibitor, was isolated as a minor metabolite of Ustilaginoidea virens. The structure was determined from the spectral data and by chemical interrelation to ustiloxin B through reductive removal of the sulfoxide-containing side chain of ustiloxin B to give ustiloxin F. Ustiloxin F inhibited microtubule assembly with an IC50 value of 10.3 microM.

Synthesis and anti-tubulin activity of ustiloxin D derivatives.

Ustiloxin D, produced by the rice plant pathogen Ustilaginoidea virens, exhibits potent anti-tubulin activity. In order to elucidate the effects of functional groups in ustiloxin D on its activity, several derivatives were synthesized and their anti-tubulin activities were estimated. The N,N-dimethylamino derivative and the 14-O-methyl derivative were inactive (IC50 > 50 microM). 20-Hydroxymethylated ustiloxin D showed decreased inhibitory activity compared with ustiloxin D.

Immunological function and nutritional status in patients with hepatocellular carcinoma.

BACKGROUND/AIMS: Infection is a major complication associated with increased morbidity and mortality in patients with hepatocellular carcinoma. We compared the immunological function and nutritional status in 16 patients with hepatocellular carcinoma (13 patients had liver cirrhosis) with those of 21 normal healthy subjects. METHODOLOGY: The immunological function was assessed by chemotaxis and superoxide anion production by neutrophils, phagocytosis and killing activities of neutrophils and monocytes, absolute and relative number of peripheral blood lymphocytes, the percentage of peripheral lymphocyte subsets and serum concentrations of immunoglobulins. RESULTS: Although the phagocytic and bactericidal activities of monocytes and superoxide production of neutrophils were not different between the groups, the phagocytic and bactericidal activities of neutrophils and the percentage of natural killer cells were significantly reduced in patients with hepatocellular carcinoma. In the latter group, the prognostic nutrition index was significantly high compared with normal subjects, indicating a poor nutritional status. The phagocytic and bactericidal activities of neutrophils were low in patients with a poor nutritional status compared to those with a good nutritional status. CONCLUSIONS: Our results suggest that impaired immunological competence and undernourishment may be one of the mechanisms causing increased susceptibility of patients with hepatocellular carcinoma to infection.

[Complication of infection in malnutritional status].

Recently, the therapeutic guideline has been mentioned in opportunistic infection of the compromised host, and many observations regarding complication of infection in these hosts have been reported. However, there were few reports in the relationship between infection and immune function or nutritional status. In this study, we confirmed that the nutritional status influences immune function in patients with lung cancer, hepatoma and renal failure, and that malnutrition markedly reduces their immunity. In patients after operation who where the pre-operative assessment of the nutritional status was performed an attempt to improve the nutritional status has been already made to improve their prognosis. Therefore, we emphasize that the management of the nutritional status even in hosts with many other diseases is thought to be important in protection against infection and prognosis of the disease.

[Roxithromycin treatment in patients with chronic lower respiratory tract disease--its clinical efficacy and effect on cytokine].

We demonstrated the efficacy of "long term" roxithromycin (RXM) treatment in 15 patients with chronic lower respiratory tract disease (11 with diffuse panbronchiolitis and 4 with sinobronchial syndrome). (1) Fourteen (93.3%) of the 15 patients showed improvement when assessed by the comprehensive improvement score, and they showed significant improvements in PaO2 (74.2 +/- 10.4 Torr to 84.3 +/- 10.9 Torr, p < 0.01), %VC (86.9 +/- 20.2% to 96.0 +/- 21.9%, p < 0.001) and FEV1 (1.81 +/- 0.87 L to 2.14 +/- 1.08 L, p < 0.01) after RXM treatment. (2) Neutrophils accumulated in the pre-RXM treatment bronchoalveolar lavage (BAL) fluid and decreased in BAL fluid of patients responding to RXM treatment (49.8 +/- 28.3% to 17.1 +/- 15.7%, p < 0.01). Additionally, the levels of interleukin 1 beta and interleukin 8 were significantly higher in BAL fluid of these patients than those in the healthy volunteers (p < 0.025, p < 0.01 respectively), and correlated with the neutrophil accumulation (r = 0.619, p < 0.05). These cytokines showed a decrease after RXM treatment. These results indicated that RXM acts by reducing pulmonary inflammation through reduction of neutrophil migration to inflammatory sites, and is effective on chronic lower respiratory tract disease.

[Analysis of cases allowed to cease erythromycin therapy for diffuse panbronchiolitis--comparative study between patients with cessation of the therapy and patients continuing the therapy].

We investigated the effect of erythromycin (EM) in patients with diffuse panbronchiolitis (DPB) who were divided into 2 groups, the short term group with 8 patients who were treated for at least 2 years and the long term group with 7 patients who were treated for more than 3 years. Each mean value of %VC, FEV1.0, FEV1.0% and PaO2 two years after administration to these patients was improved than before administration of EM, with the exception of PaO2 in the long term group. There was no change in %VC, FEV1.0, FEV1.0% or PaO2 in each group between one year after the therapy and thereafter, with the exception of the fact that FEV1.0% in the short term group, except patients restarting EM therapy, 2 years after the therapy was significantly higher than in the long term group. One patient was readministered EM because of recurrence of DPB after cessation of EM therapy, whose %VC, FEV1.0 and PaO2, but not FEV1.0%, one year after the therapy were increased in those before the therapy. The Neutrophil proportion in the bronchoalveolar lavage (BAL) fluid in this patient was still high after the therapy (94.5%), while that in the patients with cessation of the therapy was improved to the level of less than 8%. Neutrophil proportion in BAL fluids in the patients with continuation of the therapy revealed a high or low level after the therapy. These results suggest that the patients, whose %VC, FEB1.0% and PaO2 were improved and whose proportion of neutrophils in BAL fluid reduced to a normal level compared with those before EM therapy, can be allowed to cease therapy after 2 years or more of EM therapy.

[A case of human infection with Clinostomum sp].

The genus Clinostomum is a cause of parasitic laryngo-pharyngitis. We report the 15th case of Clinostomum sp. infection in Japan. A 29-year-old female visited our hospital because of throat discomfort and expectoration of a worm by sneezing on November 17, 1997. The pharyngitis was caused by the worm. The worm was morphologically identified as the adult of the genus Clinostomum.

[Natural organic compounds that affect to microtubule functions: syntheses and structure-activity relationships of combretastatins, curacin A and their analogs as the colchicine-site ligands on tubulin].

Microtubules (MT) are cylindrical polymers of the protein tubulin (TN) alpha, beta-heterodimer, and are known to be the main component of spindles in mitotic apparatus of eucaryotic cells. MT are also involved in many other basic and essential cell functions. There are a number of natural and synthetic compounds that interfere with MT function to cause the mitotic arrest of eucaryotic cells. Such antimitotic agents show a broad biological activity, and can be used for medicinal and agrochemical purposes. On the other hand, they are important also as the biochemical tools for understanding the dynamics of MT network. Most of such antimitotic agents, with a few exceptions, bind to beta-TN. Among them, colchicine (CLC), vinblastine and taxol have played major roles in practical uses as well as in biochemical studies of MT functions. They all bind to beta-TN but their binding sites are different. We have worked on a variety of antimitotic agents that bind to either of colchicine-site, vinblastine-site and taxol-site, in discovery, structures, biological actions and/or interactions with TN. In this paper, the results of our studies on CLC-site ligands were summarized; (1) synthetic analogs of combretastatin A-4 (CBS A-4), isolated as a cytotoxic compound produced by a species of South African tree Combretum caffrum, (2) curacin A (CU-A), a cytotoxic metabolite of a marine cyanobacteria Lyngbya majuscula, and its related compounds. Interactions of these compounds with TN were studied and structure-activity relationships of these two classes of compounds were discussed.

[Two cases of multiple primary cancer involving the lung with old pulmonary tuberculosis].

We reported 2 relatively rare cases of multiple primary cancer including lung cancer accompanied by old pulmonary tuberculosis. Patient 1 was a 62-year-old man admitted to our hospital for further evaluation of an infiltrative shadow on chest X-ray films, and a cervical tumor noted 10 years earlier and thought to be thyroid cancer. A Transbronchial lung biopsy (TBLB) specimen disclosed poorly differentiated squamous cell carcinoma. A right upper lobectomy and thyroidectomy were performed. Histopathologic findings showed a neoplastic lesion adjacent to caseous necrosis with formation of granuloma consistent with tuberculosis. Also, the cervical tumor was considered to be a metastatic lymph node from thyroid papillary carcinoma. Patient 2 was a 73-year-old man with a 14-year history of treatment for transitional cell carcinoma of urinary bladder, who had been admitted to our hospital for further evaluation because of a nodular shadow observed on chest X-ray films. TBLB specimens disclosed adenocarcinoma. A right upper lobectomy was performed. Histopathologic findings revealed a neoplastic tumorlet in the same lobe. No detectable increases in serum TNF-alpha, IL-1 beta or IFN-gamma were observed in either patient. Phytohemagglutinin- and concanavalin-A-stimulated lymphocyte proliferation decreased in Patient 1. These findings suggested that the immunocompromised status of patients with cancer in addition to old pulmonary tuberculosis may contribute to the development of lung cancer.

[A case of pulmonary sarcoidosis with multiple cavitation and pneumothorax].

We describe a rare case of pulmonary sarcoidosis with multiple cavitation and pneumothorax. A 32-year-old woman was admitted to our hospital with a dry cough and an interstitial shadow with dense infiltrates in both upper lungs and cavitation in the right upper lung on chest roentgenogram and CT. Laboratory tests revealed an elevated level of serum lysozyme. BAL fluid demonstrated a high proportion of lymphocytes with an increased CD4/CD8 ratio, compatible with sarcoidosis. Transbronchial lung and skin biopsies showed evidence of noncaseating epithelioid-cell granuloma, and a diagnosis of sarcoidosis was made. Although pneumothorax appeared in the left lung on chest roentgenogram during clinical observation conservative treatment without corticosteroids or any other therapy for a follow-up period of 3 years resulted in improvement of her clinical condition and abnormal X-ray findings.

Differing effects of clarithromycin and azithromycin on cytokine production by murine dendritic cells.

Summary The macrolide antibiotics are now well known to have anti-inflammatory effects. Because dendritic cells (DCs) orchestrate immune responses, we examined the in vitro effects of clarithromycin (CAM), azithromycin (AZM) and midecamycin (MDM) on the expression of co-stimulatory molecules and production of cytokines [interleukin (IL)-10, IL-6, interferon (IFN)-gamma, IL-12p40, tumour necrosis factor (TNF)-alpha] of murine bone marrow-derived DCs by lipopolysaccharide (LPS) stimulation. A 15-membered macrolide, AZM, and a 14-membered macrolide, CAM, significantly enhanced the intensity of a co-stimulatory molecule, CD80, on DCs but not CD86 and CD40. AZM significantly increased the production of IL-10 and CAM significantly inhibited the production of IL-6 by DCs. However, a 16-membered macrolide, MDM, did not have any significant effect on these surface markers and cytokine productions. Moreover, AZM increased IL-10 and CAM decreased IL-2 productions significantly, when naive T cells derived from spleen were co-cultured with DCs treated in advance with LPS and these macrolides. These findings suggest that 14-membered and 15-membered, but not 16-membered macrolides play as anti-inflammatory agents, at least in part, through modulating the functions of DCs. However, each macrolide affects them in different ways.